“…In HPS, high levels of IFN-g, soluble IL-2 receptor, TNF-a, IL-1, and IL-6 have been demonstrated, suggesting that elaboration of activating cytokines by T-helper cells promotes activation of macrophages in this disease [2]. These cytokines depress the proliferation of progenitor cells, which aggravate the pancytopenia due to phagocytosis of the blood cells [6]. In this study, however, no further evaluations were conducted, including additional marrow examination, in vitro activity test for erythrophagocytosis, and cytokine studies.…”